Object reference not set to an instance of an object

Thats My cshtml Page

if i use any Razor Syntex in page with calling : @model myProjectName.Model.LoginModel

@model OnevisitAdminWebApplication1.Models.LoginModel
@{
Layout = null;
}
"viewport" content="width=device-width" />
Login
@Styles.Render("~/Content/css")
@Scripts.Render("~/bundles/modernizr")
@using (Html.BeginForm())
{
class="container">
class="row">
class="col-md-4 col-md-offset-4">
class="nav nav-tabs" role="tablist">
"#user" role="tab" data-toggle="tab" class="big">Login
class="tab-content">
class="tab-pane fade" id="user">
class="form-group">
class="right-inner-addon">
class="glyphicon glyphicon-envelope">
@Html.TextBox(Model.UserName)
@*class="form-control input-lg" value="UserName" id="UserName" required="" placeholder="Email Address" type="text">*@

class="form-group">

class="right-inner-addon">

class="glyphicon glyphicon-lock">

@Html.TextBox(Model.Password)

@*class="form-control input-lg" id="Password" value="Password" required="" placeholder="Password" type="password">*@